Namespaces and External Modules

Sometimes, it happens that I don’t see extension methods I have stored in an external module.
I have a library, that grows almost every day I am coding. It has some convenience methods I use a lot. Like a color to text converter, to store a 6 (or 8) byte Hex value in Json dictionaries. Other methods are to convert strings to text with the right UTF8 encoding. Also, adding columns and tables to databases are found in this library.
As I said, most of these methods are extension methods.

dim c as Color = &c006699 dim h as Text = c.ColorToText ' h = "006699"
My problem is that the .ColorToText does not always appears in the autocomplete dropdown in the IDE. Not always, sometimes it does. And I have no clue why it does, or doesn’t appear.
A work around is browsing to the external module in the project browser. Opening it, find the method, open the method. This sometimes helps. But not always.

Has anybody else seen this before?